High data rate signal transmission is a concern in many systems. Current server systems, for example, often use a set of rack mounted components or user-selected blades that work together to provide data storage, processing, and communications, and the individual components often need to communicate with each other at high data rates to provide the desired system performance. In a server system using blades, the blades, e.g., server blades and storage blades, are mounted in a common enclosure and share components such as cooling fans, power supplies, and enclosure management. In general, data signals transmitted among the blades must collectively provide high data rate transmissions, and with current technology, each data signal may have a bandwidth of about 10 Gbit/s or more.
Electrical signals generally oscillate at high frequencies to provide high data transmission rates, and the high frequency oscillations can present impedance and noise problems for electrical signals transmitted over copper wires. Optical signaling can avoid many of these problems, but optical signaling may still require complex waveguide systems or dealing with loose optical cables or ribbons. Optical signaling also requires circuits for conversion between optical and electrical signals, and the requirements for such circuits may present challenges. For example, a receiver converting a high data rate optical signal to an electrical signal for an electronic component generally requires a small-area photodiode because of the high frequency of the electrical signal, and directing the optical signal onto the small area of the photodiode generally requires use of precise and reliable alignment systems. Other methods and systems for transmitting high data rate signals that avoid the problems associated with wires and optical fibers or waveguides are sought.